Controller for electric motors.



No. 7|4,02l. Patented Nov. f8, |902.

L. G. NILSN.

CONTRGLLER FOR ELECTRIC MOTORS.

(Application led May 15, 1902.)

(H n M od e l UNITED STATES PATENT OFFICE.

LARS G. NILSON, OF NEV YORK, N. Y., ASSIGNOR TO SIEGFRIED M. FISCHER ANDHARRY S. FISCHER, OF NEV YORK, N. Y., AND HULDAH ANDERSON,

OF DES MOINES, IOWA.

CONTROLLER FOR ELECTRIC MOTORS.

SPECIFICATION forming part of Letters Patent No. 714,021, dated November18, 1902.

Application led May l5, 1902. Serial No. 107,390. (No model.)

To @ZZ whom t may concern.'

Be it known that I, LARS G. NILSON, a citi- Zen of the-United States,and a resident of the city of New York, borough of Manhattan, in thecounty and State of New York, have invented a new and ImprovedController for Electric Motors, of which the following is a full, clear,and exact description.

This invention relates to improvements in 1o controllers for electricmotors, particularly of the class used for electric vehicles, the objectbeing to improve and simplify the mechanical construction and generalarrangement, so as to cheapen the iirst cost, reduce wear to a minimum,have all parts of easy access, and render the operation of the wholeconvenient and reliable.

A further object is to provide the contact springs or fingers with asuitable adjustment 2o and to improve the controller-lever con structionand its operating connections with the controller-drum.

I will describe a controller for electric motors embodying myinventionand then point out the novel features in the appended claims. Referenceis to be had to the accompanying drawings, forminga part of thisspecification, in which similar characters of reference indicatecorresponding parts in all the figures.

3o Figure 1 is an elevation, partly in section,

of an electric controller embodying my invention. Fig. 2 is a top planview. Fig. 3 is a section on the line 3 3 of Fig. 1. Fig. 4 is asectionon the line 4. lof Fig. 1. Fig. 5 is a detail showing a means forconnecting contact-points, and Fig. 6 is a section on the line 6 6 ofFig. 2.

Referring to the drawings, 5 designates the casing for the controllerand within which is 4o arranged the drum for carrying the contact ngersor blocks. This drum consists of a shaft 6, having bearings in brackets7 8 attached to the rear wall of the casingand secured to the upper andlower ends of the shaft 6. Between the brackets are disks 9 10,

to which contact-supporting strips 11, of insulating material, aresecured. As here shown, these strips are seated in notches formed in thedisks. The controller can be 5o made up for any number of speeds and anynumber of circuits; but in this particular instance I have shown theswitch-drum as arranged for seven strips 11, intended for sevenspeeds-five forward and two reverse. On each strip 1l a series ofcontact-blocks 12 is 55 arranged,th'e several contact-blocks of coursebeing spaced apart. I have indicated eleven of these con tactblocks. Twoblocks are used as terminals for supplying the current to the controllerand eight for motor connections 6o and one eXtra terminal forintroducing a resistance. By making connections by means of straps 13,as indicated in Fig. 5, any series or parallel combinations can be madebetween the contact-blocks.

For coacting with the contact-blocks carried by the drum I provide anequal number of contact-fingers 14, each finger 14. being mounted on aspring -yielding metal conducting-strip 15, extended from a terminal 7oblock 16, and at the opposite end the yielding strip is engaged by ascrew-rod 17, extended fr'om a post 18, and nuts 19 2O engage againstopposite sides of the strip, so that the strip may be moved inward oroutward to regulate the contacts 14 with relation to the contacts 12.This yielding plate preferably consists, as shown, of two strips, one ofhigh electrical conductivity for carrying in the current and the otherto serve as the spring. 8o

Secured to the shaft 6, above the bracket 7, is a toothed wheel 21,which has as many notches as there are speeds in the controller, plusone extra notch for the oi point. A holding device for this wheel 21consists of 85 an arm 22, pivoted to a lug 23, attached to the backboard of the casing and carrying at its free end a roller 24 forengaging with the said wheel 21, and the roller is heldyieldinglyinsuchengagementby meansofaspring 9o 25. It will be noted thatthe side edges of the teeth of the wheel 21 are curved, so that thespring, acting upon the arm 22, will operate with sufficient force torotate the wheel until the roller 24. reaches the bottom of a notchbetween teeth, which position corresponds to some point on or on? thecontroller.

Operating in lugs 26 27 on the upper side of the wheel is a cushion-pin28, which is moved forward by means of a spring 29, arranged between thelugs 27, and a pin 30, passed through the cushion-pin 28. At the IOOopposite side on the upper surface of the wheel 2l is anothercushion-pin 3l, operating in lugs 32 33 and moved forward by means of aspring 34.

The controller-lever 35 has a hub portion 36, which engages over the endof the shaft 6, and on this hub portion is a projection 37, designed toengage between the inner ends of the cushion-pins 28 and 3l. In Fig. 2it will be noted that the top plate 38 of the casing has an offsetopening 3%), which permits the portion 37, carried by the lever 35, topass to the under side of the top of the casing, while the hub portion36 passes through an opening to engage with the shaft. The position ofthis opening 39 is such, however, that thelever can only be placed inposition or removed when the switch-drum is on an off point. When thelever is turned, the projection 37 will press against one or the otherof the cushion-pins, compressing its spring; but as the spring 25 holdsthe roller 24 against the wheel 2l with considerable force theswitch-drum will not turn until the said projection 37 reaches the innerlug engaged by the cushion-pin upon which the said projection isbearing. Then the drum will be moved with the controller-lever, forcingthe roller 24 out until it has reached a point between notches of thewheel 2l. Then the spring of the cushion-pin will cause the drum to movesufficiently to permit the roller 24 to fall into the space .betweenteeth of the wheel 2l. Therefore it is impossible to leave the drum inany position except on some proper point on or entirely off.

In order to prevent accidental reversal of the motor, the top plate 38of the casing is provided with lugs 40 4l, against which the lowerenlarged portion 42 on a rod 43, passing through a longitudinal bore inthe lever-handle 44, engages. The lugs 40 and 4l are beveled on theirunder sides, as clearly indicated in Fig. 6, in such manner as to permitthe lower enlarged portion 42 of the rod 43 when the rod is pressed downto pass underneath the lugs, so that the lever can be moved into one ofthe reversed positions. The enlarged portion 42 is normally held upward,however, to engage with the lugs by means of a spring 45, arranged inthe handle of the lever; but when bringing the lever from the iirstreversed point to the off position it is not necessary to press the rod43 downward, as the enlarged portion 42 is beveled on its upper side, asclearly indicated in dotted lines in Fig. 6, the bevel being in anopposite direction to the bevel of the lugs 40 and 41. This permits theenlarged portion to pass downward below the lugs, so that the lever canbe moved in the opposite direction.

It will be understood that when in off position the lever is normally onthe forward side of the lugs.

Having thus described my invention, I

claim as new and desire to secure by Letters Patentl. In a controllerfor electric motors, a contact-carrying drum, a series ofcontact-fingers, yielding devices supporting the fingers, each of saiddevices consisting of a strip ot' metal of high conductivity, and aspringplate, the said supporting devices being connected at one end witha terminal, and adjusting means at the other end, substantially asspecified.

2. In an electric controller, acasing, ashaft arranged in the casing, aseries of strips of insulating material carried by said shaft, a seriesof contact-blocks carried by each strip, contact-fingers havingconnection with motorterminals, spring-yielding plates on which saidlast-named contact-fingers are mounted, and means for adjusting saidplates, substantially as specified.

3. In a controller for electric motors, a casing, a contact-drumarranged in the casing, fixed contact-s in the casing, a toothed wheelon the upper end of the shaft of said drum, an arm mounted to swing inthe casing, a roller carried by said arm for engaging With the wheel, aspring for holding the roller in yielding engagement with the wheel, acontroller-lever engaging with the shaft, a projection on said lever,and cushioned pins mounted on the wheel at opposite sides of saidprojection, substantially as specified.

4. A controller for electric motors comprising a casing, acontact-carrying drum mounted to rotate in the casing, a toothed Wheelattached to the upper end of the shaft of said drum, an arm mounted toswing in the casing, a roller carried by said arm, a spring for holdingthe roller in yielding engagement with the toothed wheel, anoperating-lever adapted for engagement with the shaft, a projection onthe hub of said lever, lugs mounted on the toothed wheel, andspring-pressed pins operating in said lugs at opposite sides of the saidprojection, substantially as specified.

5. A controller for electric motors comprising a casing, acontact-carrying drum mounted to rotate in the casing, anoperating-lever therefor, lugs extended upward from the top of thecasing and spaced apart, the said lugs being beveled on their undersides, a rod movable in the handle of the lever, and an enlarged portionon the lower end of said rod -I adapted for engagement with said lugs,the said enlarged portion being inclined or beveled on its under side,substantially as specified.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

LABS Gr. NILSON.

Witnesses:

JNO. M. RITTER, C. R. FERGUSON.

